The Effect of Duolingo on English as Foreign Language University

Students’ Vocabulary Mastery

Liya Astarilla D. W.

STMIK-AMIK Riau, Pekanbaru, Riau, Indonesia

Keywords:

Effect, Duolingo, Vocabulary, Mastery.

Abstract:

The objective of this research was to investigate the effect of Duolingo on EFL university students’ vocabulary

mastery. The method used in this study was experimental which included experimental group and control

group design with pre-test and post-test. The sample of this study was 60 students at third semester at Islamic

State University of Sultan Syarif Kasim Riau in Pekanbaru – Riau, Indonesia. The 30 students were randomy

and equally assigned as experimental group and another 30 students as the control group. The instrument of

this research was multiple choice test used as pre-test and post-test to asses the students’ vocabulary ability in

experimental and control group. In analyzing the data, the researcher used t-test. The ﬁnding of this research

showed that in the signiﬁcance degree of 0.05 the t-test was higher than t-table value (4.024>2.045). In other

words, there was a signiﬁcant improvement of the students’ score after using Duolingo in learning vocabulary.

Moreover, the average score of the post-test in the experimental group that used Duolingo was higher than

control group that only used conventional method learning vocabulary. In conclusion, Duolingo application

was effective to increase the students’ vocabulary mastery.

1 INTRODUCTION

English is very important language that used in ev-

ery aspects of life all over the world. In fact, since

Asian Economic Community (MEA) has been ap-

plied, university students should concern to prepare

themselves to compete in international job market af-

ter graduating from their college. It the other words,

beside having good education background, the stu-

dents should also have good English skills. English

become a promising skill that they should have for

their future endeavour. For example, when they want

to apply a job in a big company, they must write an ap-

plication letter and have interview in English. Then,

in the working world, they must communicate and co-

operate with many people from difference countries

by using English. It means that English is a promi-

nent factor that must have for all university students.

However, if the students want to improve their En-

glish skills, they must develop their vocabulary ﬁrst.

In learning English, vocabulary plays an important

role because it is one element that connects to the En-

glish skills namely speaking, listening, reading and

writing. “Without grammar very little can be con-

veyed” (Thornbury, 2006). Then, vocabulary is inte-

grated into every content area and is addressed as part

of the curriculum which means the use of vocabulary

is part of writing, reading, speaking, and listening.

This knowledge is the foundation of effective commu-

nication (Ababneh, 2013). In other words, students

should have adequate number of words, thus they can

use them appropriately to communicate well in En-

glish.

In Indonesia, vocabulary is not a particular subject

but has been taught within English skills namely read-

ing, writing, speaking and listening. It means that,

the students gain new words or learning vocabulary

while they are learning reading, writing, listening and

speaking. There are two types of vocabulary namely

active or productive vocabulary and passive or recep-

tive vocabulary. Productive vocabulary is the words

that the learners can understand and pronounce cor-

rectly that use constructively in speaking and writing.

Whereas, receptive vocabulary is the words that learn-

ers used in the context of reading and listening ma-

terial (Webb, 2008). However, students should have

productive and receptive vocabulary in order to help

them in learning English.

because it has a wide range, and also the va-

riety of vocabulary to be learned, including words,

phrases, collocations, idioms, etc. There are also

some kinds of vocabulary, one of them consist of part

D. W., L.

The Effect of Duolingo on English as Foreign Language University Students’ Vocabulary Mastery.

DOI: 10.5220/0009104502090215

In Proceedings of the Second International Conference on Social, Economy, Education and Humanity (ICoSEEH 2019) - Sustainable Development in Developing Country for Facing Industrial

Revolution 4.0, pages 209-215

ISBN: 978-989-758-464-0

209

of speech namely noun, pronoun, verb, adjective, ad-

verb, preposition, conjunction, and determiner (Mc-

Carten, 2007). Vocabulary learning is often boring

for the students, especially for those who grew up in

the digital era where internet has opened up a world of

possibilities for improving learning target vocabular-

ies of students (Turgut and

Irgin, 2009). However, vo-

cabulary is something that cannot be completely mas-

tered in a short duration of time but expands and deep-

ens over the course of a lifetime (Hayes et al., 1996).

In other words, learning vocabulary is a hard work, so

attempt is required to understand, produce and manip-

ulate the target words. It also need times to develop

and master this knowledge.

Based on the researcher’s experience and obser-

vation, the students’ largest problem in learning En-

glish was the lack of vocabulary. There were several

reasons that caused the students were lack of vocabu-

lary. First, most of the students seldom enhanced their

vocabulary outside the classroom. They only relied

on the lessons given by the lecturer in the classroom

which was only once a week. They only waited for

the lecturer’s instruction to improve their vocabulary

for example in the form of exercises. Due to the lim-

itation of vocabulary, the students were reluctant to

use their English whether in spoken or written form.

It triggered them become passive students. Conse-

quently, they were not interested in learning English

and it could inﬂuence their motivation too. Then, the

researcher also saw many students played games on

their smartphone after class dismissed whether in the

classroom or outside classroom. Thus, the researcher

asked several students about the exhilarated of play-

ing games. They said that playing games was fun,

challenging, and addicted. They also said that it could

overcome their stress feeling after studying all day

long.

Based on this phenomenon, the researcher thought

that playing games could become one method to en-

gage the students interest to participate actively in

learning activities, especially in learning vocabulary.

They could enjoy playing games and learning some

new words at the same time. This idea also supported

by Neyadi (Al Neyadi, 2007) who stated that one

way to master vocabulary and to develop vocabulary

bank is by applying vocabulary games in learning pro-

cess. It can help improve vocabulary proﬁciency and

also help with memory enhancement. In other words,

games could be useful to engage the students’ inter-

est to gain new words of learning vocabulary in a fun

way. Further, the application of educational games

in classroom or outside classroom can reduce inhibi-

tion among shy and weak students to participate in the

games as a result learning vocabulary become more

interesting, relaxing, motivating, and playful for the

students. It has a big role to the students’ vocabulary

improvement. These pilot studies really triggered the

researcher to ﬁnd an online educational games for her

students.

There are several educational games that re-

searcher could choose to help students’ in learning

vocabulary. However, it was necessary to choose

suitable games for the students. The games should

be appropriate with students’ level and easy to use.

There are several factors to consider the appropri-

ate language games that will be applied in teach-

ing and learning activities. First, the games should

be integrated into the existing curriculum (Harris,

2009). Second, the games should meet the objec-

tives of the topics being taught (McCarten, 2007).

Then, the lecturer’s personal beliefs on teaching ped-

agogy (Van De Bogart, 2009). Furthermore, after

the researcher overviewed and tried several educa-

tional or language games application on her smart-

phone for several weeks, she considered to use a lan-

guage games mobile application called Duolingo. It

is a freemium language learning platform for smart-

phone, android, or computer created by Luis Von Ahn

and Severin Hacker in 2011. It is one of the most

and praised language teaching application on the mar-

ket. It has also won several awards as best education

start up play and learning application. Duolingo is a

very modern-looking gaming application where most

of the activities are to complete the lessons based

on translation, dictation, and pronounciation. It also

provides various topics and sub-topics namely, noun,

verb, adjective, preposition, pronoun etc (Astarilla,

2018). Furthermore, it has gamiﬁcation elements that

can motivate and engage learners in every task or ac-

tivity at anytime and anywhere. Duolingo application

meet the needs of today’s millenials or the Net gener-

ation due to its gaming qualities at the same time also

serving as a valuable learning tool (Merz, ). Duolingo

can be quite of addicting due to its cunning use of

gamiﬁcation; lingots, level, points, and so on. It could

make students spend more than 30 minutes per day

on the application and increase students’ motivation

to be persistent on learning activities (Judith Meyer,

2013). In addition, Duolingo is giving opportunity

to students to express their ideas through the technol-

ogy. It can greatly beneﬁt the learning activities by

increasing students’ engagement and improving their

performance (Marmolejo D

ıaz et al., 2017). Duolingo

allows students to make connections between their

ﬁrst language and the target language through the task

completion or during playing the games (Kelsey D.

White and Frances Siracusa, 2013). It means that

Duolingo might be the suitable language games that

ICoSEEH 2019 - The Second International Conference on Social, Economy, Education, and Humanity

210

researcher used to motivate the students to learn En-

glish especially learning vocabulary.

The studies conducted by the previous researchers

proved that the use of Duolingo could support

students in learning English. The application of

Duolingo contributed to increase students’ English

ability and also boost their motivation in learning En-

glish. Although few studies have been done on the

use of Duolingo in improving students English skills

namely, grammar, pronounciation, speaking, read-

ing and so on, but more information on Duolingo

still needed especially on students vocabulary learn-

ing. Furthermore, based on the explanation described

above, the researcher encouraged to apply Duolingo

for her students in a blended learning environment.

This study is a kind of an experimental research.

The objective of this research was to investigate the

effect of Duolingo application on EFL university stu-

dents’ vocabulary mastery. This study used pre-test

and post-test in the experimental and control group

to investigate the students’ vocabulary mastery before

and after treatments during one semester.

2 METHOD

2.1 Research Design

This study is a kind of an experimental research.

This research conducted to investigate the effect of

Duolingo application on EFL university students’ vo-

cabulary mastery. This study used pre-test and post-

test in the experimental and control group to investi-

gate the students’ vocabulary mastery before and after

treatments.

2.2 Participants

This research was conducted at Islamic State Uni-

versity of Sultan Syarif Kasim Riau, on the third

semester majoring in Information System of the 2018

academic year. The participants of this study con-

sisted of 60 students, 30 students were randomly and

equally assigned to the experimental group and the

other students as control group. Their ages range from

nineteen to twenty one. They were enrolled in English

III course. According to CEFR it was B2 level.

2.3 Data Collection and Analysis

The technique of collecting data in this research used

quantitative research. It is used numerical and mathe-

matically methods or statistics in its explanation to get

the result of the research (Muijs, 2010). The length of

the semester was 14 weeks or meetings, where every

meeting covered 100 minutes once a week. In this

study, the researcher only gave treatment during 10

weeks for experimental group.

Blended learning model was used in learning vo-

cabulary of the experimental group by using Duolingo

while the conventional method was used in control

group. For experimental groups, Duolingo was used

outside classroom to support face-to-face meetings in

the classroom. All of the participants in experimen-

tal group have smartphone or android and they did

not know about Duolingo before. The researcher con-

ducted this research based on following design to in-

vestigate the effect of Duolingo on EFL university

students’ vocabulary mastery, as shown on ﬁgure 1.

This study used experimental group and control

group design with pre-test and post-test. Both of

groups got pre-test in the ﬁrst meeting and post-test in

the last meeting. Further, instrument of this research

was multiple choice tests which consist of 30 ques-

tions to measure students’ vocabulary mastery. The

test duration was around 60 minutes. The test items

were devised based on the syllabus and the students’

textbooks. The researcher considered using content

validity where the test items in an instrument reﬂects

the content or the syllabus in an instructional program

(Boudreau et al., 2001). Further, the researcher dis-

cussed the test items with her colleagues or experts.

Due to the content validity is using judgemental ap-

proach where the research instrument is validated by

experts or judges (Hooghe et al., 2010) and there is

no formula or statistic in constructing an insrument

(Gay et al., 2011). Before administering the pre-test,

the researcher analyzed the realibility of the test in-

trument in order to determine the quality of the test

and whether it was valid to be used in this research

through Try-out test to the other class that has the

same characteristic with the partipants. The result

showed that the reliability calculated through Cron-

bach’s Alpha formula was 0.73. It means that the test

was categorized into high reliability and acceptable.

At the ﬁrst meeting, pre-test was conducted to

both of groups in order to know students’ English

vocabulary before treatment. At the second meeting,

the researcher introduced Duolingo to the experimen-

tal group. She explained and asked all students to

download Duolingo application into their smartphone

and/or android and registered by using their email.

Because when the researcher gave an assignment, the

students would receive notiﬁcation via email that they

have assignment, which topic that they should accom-

plish, and also the deadline or the schedule of the task

submission. Then, the researcher guided the students

The Effect of Duolingo on English as Foreign Language University Students’ Vocabulary Mastery

211

Figure 1: Research Design

how to play and learn vocabulary through Duolingo.

At the third meeting, the researcher arranged a web-

site for Duolingo Classroom where all of the par-

ticipants were registered to the link by entering the

classroom password informed by the researcher. Fur-

ther, the students’ acitivities and progress automati-

cally could be monitored and seen by the researcher

on Duolingo website. Thus, the researcher also re-

ceived notiﬁcation from Duolingo on her email about

the students’ progress in detail such as it showed the

information about the students’ assignment submis-

sion time. The researcher could know those students

who submitted the assignment on time, late, or even

did not submit her or his assignment on Duolingo.

The researcher used semi structured assignment on

Duolingo. Sometimes, she arranged which task that

students should accomplish and for other days the stu-

dents could choose which task that they wanted to ac-

complish on Duolingo. For the next meetings, the re-

searcher encouraged the students to play and learn vo-

cabulary through Duolingo before the class meeting,

after class meeting, during meeting or outside class-

room at least 10 minutes in a day. For example, before

the class meeting was started, the lecturer gave time to

the students to play Duolingo while she was checking

the students’ attendance list.

Furthermore, the researcher monitored the partic-

ipants who were actively playing the games by look-

ing at the leader-board every single day. The students

also competed and communicated with their friends

or users by giving comments. It means that the stu-

dents could play and learn vocabulary individually

or in group through battle and discussion with their

friends anywhere and anytime. Whereas, for con-

trol group the participants only learning vocabulary

by using conventional method without the application

of Duolingo in teaching and learning activities. This

group only learnt new words in sentences, texts, and

passages, and tasks on their textbooks.

After conducting the treatment for 10 weeks,

at the end of the semester the post-test for both

groups were administered by the researcher in order

to know the achievement between the experimental

group which using Duolingo and control group which

using conventional method. In analizing the data, the

researcher used Statistical Package for Social Science

(SPSS) 24 version. Descriptive statistics were used

to investigate the means and standard deviation of

each variable. Then, the researcher compared both

of groups’ score before and after the treatment con-

ducted. Thus, t-test paired sample test was analyzed

to determine differences between the means of both

groups. This technique was useful to show statisti-

cally whether there were any differences scores be-

tween the experimental group and control group or

not.

3 FINDING AND DISCUSSION

At the beginning of the research, the researcher used

pre-test in order to investigate the equivalence of the

vocabulary mastery of the experimental and control

groups. Then, the result the of pre-test of both of the

groups were examined in order to know whether there

was any signiﬁcant differences between experimental

group and control group before the experiment. Thus,

t-test paired sample test was conducted. The statistics

of the scores are presented in Table 1.

Table 1 describes that the mean score in the pre-

test is 55.44 (SD= 9.96) in the experimental group and

56.33 (SD= 8.93) in the control group. It shows that

there is no signiﬁcant difference in the mean score of

the pre-test at the 0.05 level (t= -0.32, P>0.05). It em-

phasizes that participants between experimental and

control group do not show any difference in vocabu-

lary mastery. This result reveals that both of groups

were homogenous and have the same level of ability

ICoSEEH 2019 - The Second International Conference on Social, Economy, Education, and Humanity

212

Table 1: Result of t-test Paired Sample Test on Pre-test.

Description N Mean SD t df Sig.(2-tailed) (P Value)

Pre-test Experiment 30 55.447 9.966 -3.079 29 0.707

Pre-test Control 30 56.333 8.939

before conducting the treatment.

Then, to investigate whether there was any differ-

ence on students’ vocabulary mastery in the post-test

within the groups after treatments a t-test paired sam-

ple test was conducted. The result could is shown in

the Table 2.

Table 2 reveals that there is a statistically differ-

ence between experimental group and control group

on the post-test (p<0.05). The mean score of the ex-

perimental group is 76.66 (SD=7.87), while the mean

score of the control group is 67.55 (SD=9.34). There

is improvement on both groups scores from the pre-

test to post-test.

Then, by comparing t-test and t-table p<0.05,

we can concluded that t-test was higher than t-table

value (4.204>2.045). Therefore, it means that the

null hypothesis (H0)that stated there was not signif-

icant effect of Duolingo on EFL university students’

vocabulary was rejected. Thus, alternative hypothe-

sis (Ha) that stated that there was signiﬁcant effect of

Duolingo on EFL university students’ vocabulary was

accepted.

Table 3 describes that there are improvements of the

students’ score by the two groups on the post-test

compared to the pre-test results. But, the experi-

mental group’s vocabulary mastery improved much

better after the treatment. The students that applied

Duolingo in learning vocabulary gained higher score

than the students who did not apply it. The results

show that, the mean score of the experimental group is

higher than control group on the post-test. The mean

score in the pre-test is 55.44 (SD=9.96) become 76.66

(SD=7.87) in the post-test of the experimental group.

Then, the mean score in the pre-test is 56.33 become

67.55 (SD=9.34) in the post-test of the control group.

It could be concluded that Duolingo could improve

the students’ vocabulary mastery.

This ﬁnding was in line with several researchers’

ﬁndings. Ana (de Castro et al., 2016) found that

Duolingo contributed to increase the vocabulary of

her students at IFF language centre. There was a sig-

niﬁcant improvement on her B2 students’ score af-

ter using Duolingo in learning vocabulary. This ﬁnd-

ing also coincided with Ahmed (Bahjet Essa Ahmed,

2016) study who stated that Duolingo could promote

acquiring vocabulary for beginners. He found that

there was improvement on his students’ score on the

test. These ﬁndings were correct as the ﬁndings of

the researcher in this research that using Duolingo

could help the students in learning English and im-

prove their vocabulary mastery.

To sum up the improvement of students’ scores

before and after conducting the research, the re-

searcher created a chart. The result of the scores could

be seen in Figure 2.

Figure 2: Learning Improvement Chart

Figure 2 describes that there is about 38% im-

provement on the experimental group or those stu-

dents’ who learned in blended learning vocabulary

through the use of Duolingo. Whereas, there is

about 20% improvement on the control group or

those students who learned vocabulary in conven-

tional method. Therefore, it can be concluded that

Duolingo is effective in improving EFL university

students’ vocabulary mastery. This result was also

congruent with Kusumadewi (Kusumadewi, 2018)

who found that there was a signiﬁcant improve-

ment on her students’ vocabulary mastery after using

Duolingo in teaching and learning activities. The stu-

dents who used Duolingo got higher score than who

did not on the test.

Finally, the researcher assumes that the use of

Duolingo in learning vocabulary gave signiﬁcant ef-

fect on EFL university students’ vocabulary mastery.

From the result, it was clear that there were differ-

ences between students’ score before and after the

treatment. The researcher realized that this technique

must have strengths and weaknesses. For Duolingo,

the strengths found by the researcher in teaching and

learning vocabulary, those are:

a) Duolingo engaged the students’ enthusiasm and

their motivation in learning vocabulary,

The Effect of Duolingo on English as Foreign Language University Students’ Vocabulary Mastery

213

Table 2: Result of t-test Paired Sample Test on Post-test.

Description N Mean SD t df Sig.(2-tailed) (P Value)

Pre-test Experiment 30 76.667 7.877 4.204 29 0.000

Pre-test Control 30 67.550 9.346

Table 3: Result of Descriptive Statistic.

Description N

Pre-Test Post-test

Mean Std. Deviation Mean Std. Deviation

Experiment Class 30 55.45 9.966 76.67 7.877

Control Class 30 56.33 8.939 67.55 9.346

b) It supported the students’ learning activities any-

time and anywhere,

c) It enriched the students’ vocabulary in a fun way.

This ﬁnding is congruent with Natanael and By-

ron (Marmolejo D

ıaz et al., 2017) concluded that

Duolingo is a practical and useful application that

could be used as a Foreign Language courses to im-

prove students’ skills and to create students’ motiva-

tion. This result also in line with Astarilla (Astar-

illa, 2018) who found that Duolingo could use to sup-

port the students in learning process. The ﬁndings

revealed that students had an overall positive percep-

tion towards the use of Duolingo application in learn-

ing English. The ﬁndings described that more than

80% of the 135 participants agreed the features in

Duolingo was easy to use, convenient and fun. They

could access it at anytime and anywhere. Then, they

also thought that Duolingo could develop their self-

learning skill and encourage them to learn English.

As a result, it could increase their motivation to learn

and to practice their English skills not only in the

classroom but also outside the classroom. In conclu-

sion, Duolingo was effective to improve the students’

motivation and their vocabulary mastery.

4 CONCLUSION

This study investigated the effect of Duolingo appli-

cation on EFL university students’ vocabulary mas-

tery. After conducting this research and calculating

the data from pre-test and post-test scores of the ex-

perimental and control groups, it showed that the re-

sult of t-test was 4.024 while the value of t-table was

2.045 in the signiﬁcance degree of 0.05. It described

that t-test was higher than t-table value. It means

that the null hypothesis (H0) that stated there was not

signiﬁcant effect of Duolingo on EFL university stu-

dents’ vocabulary was rejected. Thus, alternative hy-

pothesis (Ha) that stated that there was signiﬁcant ef-

fect of Duolingo on EFL university students’ vocab-

ulary was accepted. It also could be seen from the

mean score of the experimental group was higher than

control group on the post-test. The results showed

that the mean score in the pre-test is 55.44 (SD= 9.96)

become 76.66 (SD= 7.87) in the post-test of the ex-

perimental group. Then, the mean score in the pre-

test was 56.33 become 67.55 (SD= 9.34) in the post-

test of the control group. These results describe that

there were improvement on vocabulary mastery by

the two groups on the post-test. But, the experimen-

tal group’s vocabulary mastery improved much bet-

ter after treatment. Therefore, it could be concluded

that Duolingo was effective in improving EFL univer-

sity students’ vocabulary mastery. Based on the ﬁnd-

ing of the research, the researcher recommends to the

teachers and lecturers to apply Duolingo for devel-

oping their students’ vocabulary because this applica-

tion can support the students’ vocabulary learning and

motivate students to learn English anytime and any-

where. The researcher also hopes other researchers to

continue conducting future researches related to the

use of Duolingo on other English skills.

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